In a fireside chat on Thursday, CNBC's Jim Cramer told a caller that in the cryptocurrency markets, bitcoin seems to have a slight leg up against its fast-growing rival, Litecoin.

The "Mad Money" host said that the future of any cryptocurrency will hinge on the depth of its market and the disparity in futures prices.

That's why Cramer found it "crazy" that bitcoin futures, which are now listed on different exchanges, are so differently priced on each exchange.

"You can't have futures be that off," he said. "What you're looking for is a market that is more transparent and has one price to it. I think the Lite[coin] market is probably going to be less deep than bitcoin because of the first-mover advantage."

Litecoin, the world's fourth-largest cryptocurrency by value, has rallied 5,800 percent in 2017, trouncing even the parabolic rise in bitcoin.